[Info-vax] Programming the serial port on an Alphaserver 200

[Michael Moroney]

rtk <oneelkruns at hotmail.com> writes:

>Ok, first, thanks for all the many helpful comments!

>I got things to the point where I can send bytes out the port with a
>simple C program using fopen() and fputc().  The string I send out is
>preceded by a 0x0A, however.  When I try to read bytes sent to the
>port the program hangs.  If I look at the output of SHOW DEVICE/FULL
>_TT it shows TTB0 as using formatted I/O which is not what I want.
>Also, I haven't found how to open the port for reading and writing at
>the same time.

You'll need to work on a lower level than what the C RTL provides.
See the terminal driver portion of the I/O User's Reference Manual.
Using the $QIOs specified will tell you how to issue writes without
C inserting extra linefeeds, and issue reads without waiting (apparently)
for a return at the end.  Unfortunately, not so easy at first.